Three-phase current transformers have been known heretofore. However, these prior three-phase transformers generally have been constructed by mounting three, individual coil-core subassemblies separately on a support or mounting panel, thus requiring more panel space and having more mounting problems than would be the case with a unitary transformer. Prior three-phase transformers have also been constructed by encapsulating all three-coil-core subassemblies in a mass of molding or casting material of the electrical insulating and heat conducting type such as plastic. However, such cast construction cannot be disassembled for repair or replacement of parts without destroying it.
While these prior plural-phase current transformers have been useful for their intended purpose, it has been found desirable to provide an improved three-phase current transformer overcoming the aforesaid disadvantages.